Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 1894

September 5, 201213 counties in Oklahoma; 20 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Sep 5, 2012, 2:49 PM CDT for 13 counties in Oklahoma; 20 counties in Texas. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued
Sep 5, 2012, 2:49 PM CDT (19:49 UTC)
Expired
Sep 5, 2012, 3:45 PM CDT
In force
56 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 33 counties

Beckham County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Greer County, OK, Harmon County, OK, Harper County, OK, Jackson County, OK, Major County, OK, Roger Mills County, OK, Washita County, OK, Woods County, OK, Woodward County, OK, Armstrong County, TX, Briscoe County, TX, Carson County, TX, Childress County, TX, Collingsworth County, TX, Cottle County, TX, Donley County, TX, Gray County, TX, Hall County, TX, Hardeman County, TX, Hemphill County, TX, Hutchinson County, TX, Lipscomb County, TX, Motley County, TX, Ochiltree County, TX, Potter County, TX, Randall County, TX, Roberts County, TX, Swisher County, TX, Wheeler County, TX

The radar

The Amarillo radar (KAMA), 124 km from the middle of the area, began a volume at 19:50 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 7.8 hours before the alert went out and 123 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Amarillo Airport, TX at 12:00Z on 2012-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1415 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Amarillo Airport, TX at 12:00Z on 2012-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 49 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1415 J/kg
Mixed-layer CIN
-182 J/kg
Mixed-layer LCL
1651 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
66 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 5, 3:19 PM CDTSevere Thunderstorm WatchSPCBeaver, Texas8 hr
Sep 5, 3:56 PM CDTSevere Thunderstorm WatchSPCAlfalfa, Blaine, Custer, Dewey, Ellis, Garfield and 7 more7 hr
Sep 5, 6:53 PM CDTMesoscale DiscussionSPCAlfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 16 more67 min

Nearby

Mesoscale Discussions in Texas, 2012Mesoscale Discussions in Oklahoma, 2012Every mesoscale discussion in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.